We've seen homages to their prior songs/works on their Instagram in the lead up to Queendom (and in the Queendom MV teaser), as well as individual member teasers for Queendom and various comments/visuals that hint to their former songs. While I think it's a wonderful notion, I believe they're doing it to cap off their seven-year career.
RV has never quit their contracts (to my knowledge), and the fact that all of their teasers are memories of their previous works leads me to assume this is their final reunion.
Im not trying to be negative but this is kpop afterall . Unexpected disbandment always happen like SISTAR,4 Minutes and GFRIEND . anyway this is just some theories from other forum