No age limit to the SAS. That just doesn't sound right.
I queried service with the RM reserve and for told '32 years old max, but small possibility of a waiver'. And the bootnecks are conventional forces.
You could phone up 0800 587 2825. The MoD website is pretty much up to date though the training programme has changed again slightly with fewer weekends and longer collective training periods.
21 & 23 SAS processes applications from male and female applicants, with no previous military service. Applicants must be no older than 42 years 6 months when applying to join the Army Reserves (AR). They will then be sponsored out to their recommended local AR unit to complete basic training and gain experience before being allowed to attempt SAS Reserves Selection.
Ex Regular and AR applicants must be no older than 43 years 364 days on weekend 1, of the Selection Induction Weekend (SIW) of SAS(R) Selection.