Typically every two years alternating between irons and woods. With the new naming convention, yes, it will be a bit more difficult to quickly track legacy clubs to their release date but most folks here will remember. TS woods had a bit of a gap between the main TS2/TS3 and the recent announcement to release TS3/TS4 versions. Concept irons have been added in between iron set releases. Next generation of irons will have a completely different numbering system as indicated by recent announcements of the T100 but 620MB and 620CB appear to keep the old "20 for 2020" naming. Historical release dates have usually been the fall of the previous year a club is numbered (718's released in the fall of 2017).

Apparently the AP irons are being differentiated from 620 CBs and MB. T100-T400 will apparently replace (in order) AP2, AP3, AP1, and another game improvement additional iron (T400), sort of corresponding to the TS1 driver. All the iron lines should be released this fall. Unless the T400 is delayed like the TS1 and TS4 were delayed from the TS2/3 introduction. This is from rumors/pictures posted on sites like GolfWRX and not by Titleist.

I have a fitting coming up soon at the Titleist Fitting Centre at St Ives
Can’t wait to try out these beauties

I would like to know if the t 100 t200and t300. are they forged and what are the specs

Similar to the AP2, AP3, and AP1, the heir apparents are the T100, T200, and T300. Like the AP2, only the T100 is forged. No knowledge of the specs, although unlikely the lofts will change. The site lines and inner materials are changing for most of the improvements.

U 500 Utility and TS hybrids release date?

Thats quite interesting

i like it very much