Hello
It shouldn't matter *that* much, except for the input filters; the resonant LC tank is at its switching frequency. Of course, it depends on its internals for which, I cannot say anything.
But, for some comforting thoughts, if you have access to some testing facility and if it has the possibility of adjusting the power output, you might be able to connect it to an autotransformer with 150V, for example, and gradually start its power from zero. If it won't work, gradually increase the input voltage and repeat the process, while doing measurements.
Vlad