If the first line indent differs from the hanging indent (i.e. the first line indent marker is to the left of the hanging indent marker), then the first, and only the first, tabstop to the right of the hanging indent is ignored. Obviously, if the firstline indent is the same as the hanging indent, then the first tabstop is OK.... only when they differ is the first tabstop to the right ignored.
Simple to demonstrate, but I'll send you an example if you want.
WPTools 5.18.8, D7
As usual, this is a rather critical issue! :)
Eric