PHPBB moved topic will not loose Google URL? 301 redirect?

Hello,

i want to ask if in PHPBB i move topic to another forum folder, will google still resolve their indexed URL of this topic to its new destination?
I mean if there is any redirect, or URL is not changed? Im not using any URL rewriting.

My topic URL
http://myforum.com/viewtopic.php?f=133&t=1387

and after i moved that topic, i still can access it thru above URL, and when i checked that URL agains redirect checkers, that URL appears like a direct link, not redirect, returns http code 200 (ok).