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I doubt that there was much of a chance of them dumping BCC in the first place.
who exactly are "them"? we still don't know who does this address belong to apart from speculating about it.
If they wanted to secure their wallet because of the 1st August bitcoin cash fork, then they would have done so by transferring the entire cold storage to another address that they own. But the fact that they only transferred around half eliminates the possibility that they were dumping BCC.
i wouldn't jump to any conclusions yet. 124,000 bitcoin and bitcoin cash is a lot of money which you can't really sell on any of the exchanges! finding a way to dump it takes time and specially since the price is too low right now it is not a good idea anyways.
Anyways, as i said, it is likely that they want to diversify into other things or preserve some of their profits. They have made a bunch off bitcoin since last year already and probably just want to get some btc out when it's still $3000+.
if i wanted to guess i would have said this simply belongs to a service or something like that. it is their cold storage which they are now diving into, possibly because there have been withdrawals from their service.