In this case, Rosh Hashanah in 12 months 1 is postponed from Tuesday (the third deḥiyyah). As it cannot be postponed to Wednesday, it's postponed to Thursday, and year 1 finally ends up with 354 days. On the other hand, if 12 months 2 is already a short yr of 383 days, there might be a problem if TM2 is on a Wednesday. Rosh Hashanah in yr 2 must be postponed...