This discussion clarifies that there isn't a specific verification time limit for TDS returns in the same way there is for IT returns. Once the FVU file (which is the TDS return itself) is submitted to TIN-NSDL by the due date, it is processed by NSDL. Form 16A is then generated from the TRACES portal. The key is adhering to the submission deadlines for the FVU file.
16 July 2021
No such verification of TDS return is necessary. FVU file has to be filed with TIN-NSDL (or online) and the statement would be processed within a week or two. Thereafter you are required to generate form 16A from Traces portal.