Yes. Since now, t3s dont nescasarily give more plunder. Its easy ti lc as a hansel build with lvl3 guilds (cheapest bang for the buck)
The answer depends on what your long term plans are. If you plan on eventually building T3s and you don't plan on resetting, then you should start building T3s as soon as they are cheaper than your next land (after 1b land). If your goal os max plunder then you should start building L4 guilds just before the 1b land. If you plan on resetting - none of this applies. The idea is to create the most efficient revenue path by choosing the option which provides the highest plunder increase for the lowest cost. A 3bil land will leave you with a forge (~100k plunder) instead of 3 L4 guilds (~400k plunder each). The math is clear.