On appeal from the denial of his postconviction motion under Mass.R.Crim.P. 30(a), 378 Mass. 900 (1979), the defendant claims that the sentence imposed upon him by the District Court judge in the jury session was contrary to the statutory prohibition against increasing a sentence on withdrawal of an appeal under G. L. c. 278, § 25. We affirm the denial of the motion.

General Laws c. 278, § 25 (as amended by St. 1983, c. 82), provides, in pertinent part, that “[wjhere the court allows the withdrawal [of an appeal], it may order the appellant to comply with the sentence appealed from, in the same *347manner as if it were then first imposed . . . ; provided, however, that the court shall not increase the sentence as first imposed. . . .” Here the sentence first imposed upon the defendant after a District Court bench trial was a one-year commitment to a house of correction for his conviction for larceny under $250. The defendant appealed this conviction to the jury session of the District Court. While his appeal was pending, he was convicted in another division of District Court of other charges, for which he received a sentence of one year to a house of correction. The defendant then requested the withdrawal of his appeal in this case. After a Ciummei colloquy with the defendant, see Ciummei v. Commonwealth, 378 Mass. 504, 509-510 (1979), the judge in the jury session allowed him to do so and a sentencing hearing followed. The prosecutor urged that the sentence to be imposed should run from and after the one year house of correction sentence the defendant was then serving. The defendant argued that the sentence to be imposed should run concurrently with the sentence the defendant was serving. The judge reimposed a sentence of one year to the house of correction but ordered that it be served from and after the sentence the defendant was presently serving. The defendant, claiming the sentence was illegal, filed a motion under Mass.R.Crim.P. 30(a). The judge denied the motion on the ground she had not increased the sentence but simply had clarified it because of the defendant’s subsequent incarceration.

We conclude that the imposition of a consecutive sentence did not increase the defendant’s initial sentence. While it is true that the imposition of a consecutive sentence in these circumstances exposed the defendant to a longer period of confinement before he was eligible for parole than a concurrent sentence, see 120 Code Mass. Regs. §§ 201.01(1), 201.04, & 201.08,1 it did not extinguish the separate identi*348ties of the sentences. Baranow v. Commissioner of Correction, 1 Mass. App. Ct. 831, 832 (1973). If the sentence imposed in this case by the judge in the jury session is viewed separate and apart from the sentence the defendant was already serving, its imposition did not change the term of the sentence. Cf. Campbell v. Commonwealth, 339 Mass. 695, 696-697 (1959) (the imposition of an indefinite Concord sentence on withdrawal of appeal in place of a sentence of eighteen months to a house of correction deemed an increase of sentence). Nor did it change the time the defendant must serve to be eligible for parole. See 120 Code Mass. Regs. § 201.01(1), supra, note 1. It simply delayed the time that the defendant would begin serving the sentence.

The defendant also argues that the withdrawal of his appeal was involuntary, because the judge did not advise him that she could impose a consecutive sentence. We deem this issue waived, because the defendant failed to raise this issue in the postconviction motion presented to the court below. See Commonwealth v. Lowe, 405 Mass. 1104, 1104-1105 (1989); Mass.R.Crim.P. 30(c)(2), 378 Mass. 901 (1979).

Order denying postconviction relief affirmed.