With the help of paralay, now I can present modified T-60 history.
1. OKB Sukhoi is working on advanced Su-24BM modification.
2. In 1981 program B-90 started. Simonov pressed the initiative that TsAGI should develop the new planes and OKBs must build them.
3. (1982) T-4MS derived project transferred from TsAGI to OKB Sukhoi, where it received designation T-54. Oleg Samojlovich became chief designer.
4. In OKB Su, people are unhappy with, ehm, stupid solution applied on T-54 like VG wings under fuselage or two-path engines. It also killed further works on Su-24BM, so plane was completely redesigned as Sukhoi T-60.
5. In 1985, Samojlovich moved to OKB MiG and used T-60 scheme as basis of new MiG 70.1 heavy interceptor. There is attempt to use the same airframe for tactical bomber.
6. In 1987 - 1988 project was once again reworked as T-60S (S means serial - production). In Novosibirsk aviation plant started construction of a prototype. But the model didnt pass the TsAGI tests and was once again (third time!!!) reworked and once again put into production.
7. Some activity was done in 1991 - 1992 under development of a new perspective bomber.
8. The program is officially closed in 1992. Some things indicates, that it is connected with development interruption of AL-41F, so the final version of the T-60S should be powered by this engines.
9. In 2006, guys from secretprojects forum presented as first worldwide this story publicly.