Appellant contends inter alia1 that the lower court erred in denying his motion to dismiss the charges against him under Pa.R.Crim.P. 1100(f). Because we agree, we reverse and discharge appellant.
On March 5, 1977, police arrested appellant and filed a written criminal complaint charging him with operating a motor vehicle under the influence of drugs or alcohol,2 reckless driving,3 and involuntary manslaughter.4 Trial did not commence until September 29, 1977, 210 days after the filing of the written complaint. On July 20, 1977, appellant’s counsel filed a written application for a continuance in which he alleged that he would be unavailable for appellant’s trial, then scheduled for the week of July 25, 1977. The continuance application also contained the following waiver, signed by appellant:
“I am aware and have been advised of the implications and consequences of the above application and (have/do not have) objection to the continuance. I am further aware of my right to a speedy trial and that a continuance shall cause *4a delay in having said criminal charges disposed of by the Court.”
The lower court granted the continuance but for an unspecified period of time.5 On September 29, 1977, appellant’s counsel filed a written motion to dismiss the charges under Rule 1100(f). The Commonwealth and appellant’s counsel agreed on the above facts and the lower court denied the motion. Trial commenced the same day,6 which was the Thursday of the first week of the next trial session after the session of July 25. Appellant was found guilty of driving under the influence and involuntary manslaughter. On the charge of driving under the influence, the lower court placed appellant on one year probation in lieu of sentence and ordered him to pay a $200 fine and undergo treatment at an Alcohol Information Program. On the charge of involuntary manslaughter, the court sentenced appellant to IIV2 to 23 months imprisonment. This direct appeal followed.
Rule 1100(a)(2) mandates that the Commonwealth commence appellant’s trial within 180 days of the filing of the written complaint. Any delay beyond 180 days must be either excluded from the computation of days pursuant to Rule 1100(d) or justified by an order granting an extension pursuant to Rule 1100(c). Commonwealth v. O'Shea, 465 Pa. 491, 495, 350 A.2d 872, 874 (1976). When, as here, the Commonwealth has not sought an extension of time under *5Rule 1100(c), it has the burden of showing by a preponderance of the evidence that, under the operation of Rule 1100(d), enough days can be excluded from the period for commencement of trial to comply with the time limits of Rule 1100. Commonwealth v. Wade, 475 Pa. 399, 380 A.2d 782 (1977); Commonwealth v. Mitchell, 472 Pa. 553, 564, 372 A.2d 826, 831 (1977). When a continuance is properly granted because of defense counsel’s unavailability, we will exclude the entire period of the continuance under Rule 1100(d)(1). See Commonwealth v. Smith, 262 Pa.Super. 258, 396 A.2d 744 (1978). However, the Commonwealth must prove that the reason for not scheduling and commencing trial in the remaining days of the Rule 1100 period is, in fact, the unavailability of an accused or his counsel and not “judicial delay.” See Commonwealth v. Morgan, 484 Pa. 117, 398 A.2d 972 (1979). Moreover, the Commonwealth has the burden of proving that any waiver of Rule 1100 rights is valid. See Commonwealth v. Waldman, 484 Pa. 217, 398 A.2d 1022 (1979). In Commonwealth v. Coleman, 477 Pa. 400, 405, 383 A.2d 1268, 1271 (1978), our Supreme Court specifically held that waivers of precisely the same form as that which appellant signed have “no legal significance.”
Because the Commonwealth in the case at bar never applied for an extension of time under Rule 1100(c), it must prove that at least 30 days are excluded from the computation of time under Rule 1100(d). The Commonwealth may not rely upon appellant’s signed waiver because it is not valid. Coleman, supra. Even assuming defense counsel’s unavailability for the entire period from July 20,1977 to the end of the week of July 25, 1977, “it is clear that the reason for not scheduling [appellant’s] trial in the remaining days of the [Rule 1100] period was because the court calendar would not permit. Thus, the Commonwealth’s claim for excusing the commencement of trial on the days following [the admitted period of unavailability] rests upon a claim in the nature of ‘judicial delay’ rather than . . . unavailability . . . . Our cases have made clear that scheduling difficulties may provide the basis for the request of an *6extension pursuant to section (c) of the Rule rather than section (d)(1).” Morgan, supra 484 Pa. at 125, 398 A.2d at 975. See Coleman, supra. Because the Commonwealth has not shown that defense counsel’s unavailability caused a delay of 30 or more days in the commencement of trial and because the Commonwealth never obtained an extension of time under Rule 1100(c), we conclude that appellant’s Rule 1100 rights have been violated and he must be discharged.
Judgment of sentence reversed and vacated and appellant discharged.
WIEAND, J.; files a dissenting opinion.. Appellant also contends that the lower court erred in not sustaining his demurrer. Because of our disposition on the Rule 1100 issue, we need not reach the merits of this claim.
. 75 Pa.C.S.A. § 1542.
. 75 Pa.C.S.A. § 3714.
. 18 Pa.C.S.A. § 2504.
. It is unclear from the record when the lower court granted the continuance. We have only the written application before us which indicates that (1) appellant signed the waiver on July 13, 1977, (2) appellant’s counsel signed the continuance on July 14, 1977, and (3) the prosecutor’s office signed the application, thereby indicating it was not opposed, on July 20, 1977. On the bottom portion of the application, the lower court indicated that it granted the application for continuance by marking an “X” after the word “Granted” and signing it. The lower court did not date its grant. However, the application, complete with the lower court’s signature, was filed on July 20, 1977. We conclude from the above that the continuance was granted on July 20, 1977.
. Because the trial judge had not yet directed the parties to proceed to voir dire or opening argument nor taken any other such first step in the trial, appellant’s Rule 1100(f) motion was timely filed. See Commonwealth v. Evans, 249 Pa.Super. 142, 375 A.2d 799 (1977).