Hiya,
I have had the same experiences with my coolidor, until recently. If I remember correctly, the beads either release moisture, or attract moisture, until the surrounding RH is, in your case, 70%. I have read that having a fully stocked container will help to keep the humidity stable, but my opinion is that with beads, or a PG/distilled water Credo, as long as your container is air tight, the RH should stablize regardless of the how many cigars you have. However, cigars are also hygroscopic, IIRC, so if the cigars that you have in the tupperdor are all wet and mushy, they will RELEASE moisture into the air, and, depending on how wet/dry the beads are, the beads may not be able to soak that extra moisture, and the RH won't be able to drop down to the target 70%.
In my case, I kept on opening the damn coolidor to take in the sights and smells, so the atmosphere in the cooler never had a time to equalize. Also, I just threw in a bunch of cigars from JRCigar which must have been dry as a bone. Once I stopped opening the thing every hour, and let the cigars soak up whatever moisture they needed, the RH has settled dead on to 70% for the last 3 days...I am keeping my fingers crossed that it stays that way.
So, although I am no expert, and I am sure the real experts will chime in soon, I would guess that the beads have been recently recharged, and your cigar's moisture content is significantly higher than the 70% RH you are shooting for in the tupperdor. Sadly, I have no idea how you would dry out the cigars, if that is indeed the problem.
WHEW!!! I am a windbag or what!!??!