Part of the problem is
1. New accounts can renounce young status - So you can't use young status to hold off house-placing (remember- this fix was to deal with people using trial/buddy accounts to bogart plots at IDOCs to sell for RL cash).
2. All accounts start with a bonus couple of months age, and we all know how flaky account age has been, so it can't be used either.
Only the character age timer appears to work right 100% of the time, so they went for it as the means of fixing the issue.
It sucks if you're trying to arrange things for starting on a new shard, but that's a hell of a less common occurrance than those land speculators and their scripts.
Suggestion for persons who might run into this in the future.
If you know a month ahead of time that you're gonna start up on a new shard, create a character to get to 15 days old to place/trade. The house is account bound, so once it's traded, it's yours.
Even on a 9-year account, if I was gonna be starting on SP, I'd go out training for over two weeks, living out of an inn (and keeping everything of value in my bank - even stripping my gear into the bankbox before going to the inn), before even thinking of placing a house. If anything, one's home is an even less secure place in SP than on other shards, because you have to be able to survive potential PKs to get to it, no matter where it is placed.