I don't quite agree as they have a big banner hung out at school in remembrance of June 4 every year. But they do have a close connection with the Guangzhou Pui Ching school.
Technically speaking, pc should be regarded as a right wing school n should be mixed up with 培僑!
However, pc family was branched out from Guangzhou pc which was the best school in southern china(pc was formed by a group of Christians n medical doctors). hk pc was run cocurrently with Macau pc since 1933. Pchk holds lots of exchange activities with it's china n macau counterparts n maintains close relationship with each other no matter how different their individual curricula that might have been.
孫中山亦曾任培正的校董及包括他兒子孫科等及後數代人皆是培正校友,故培正離左派尚遠矣
There are some students whose parents are from New Zealand, Japan, but it's not easy to learn Chinese well in Pui Ching as the Chinese standard is quite high, especially Chinese writing and calligraphy.