Pure speculation on my part, however, I don't think we'll be getting RoS with FTP until the following expansion release. I think DBG realized when they gave TDS to FTP that having FTP and people currently buying the expansions being at the same level was bad for business.
I could see them releasing 2 expansions per level cap, and not giving FTP either of the associated expansions until live moves onto the next level cap. I know there was a dev post in the past somewhere about how expansions were supposed to release for FTP, but then that never happened with TBM and TBM/EOK were released together for FTP.
This would widen the level gap between FTP and those who buy the expansion, which in theory boosts expansion sales since people are less likely to leave a box that is often used without the expansions if they are at a further disadvantage by doing so.
I can't say for certain what DBG will do as far as FTP, but what I can say is either way I have a decent number of accounts waiting for this sale to end and the new expansion to go on pre-sale because they have been sitting at 23/25 patiently waiting to go 26/26.