danno858 My piano's tuning was fairly stable, but I would notice a change in mid winter and again mid spring. I used to have it tuned twice a year. It needed new hammers and strings and a new action and a host of other things so I just decided to go for broke and do the whole thing.
I would probably talk to the rebuilder, but I wouldn’t be surprised if in the first 1-2 years the piano would benefit from more frequent tunings. When I bought my piano, it was tuned every 3-4 months during the first two years, and particularly during the first year, it really needed it. Since then, the tuning has stabilized and I get it tuned every 6 months. My piano has had a Dampp chaser the whole time, and the climate hasn’t been wildly different.
I guess I write all this to say, don’t blame the Dampp chaser if you find your piano needs more frequent tunings! It may just be that the strings are settling in. Like @ShiroKuro , I do think the DC system helps.