There is no one answer to this question: it depends on the nature of the investments and liquidity issues. If the assets are all in a cash fund or bank account, surely a couple of days is enough. If there is real estate restricted deposit accounts or the like, it could take much longer.
Has the trust company provided a statement showing the nature and amount of the assets? That would go a long way to assuring they are acting appropriately ... a certified letter asking for an accounting and distribution is the next appropriate step if that hasn't already been done. I'd strongly suggest contacting a local attorney to insure you're doing this right!