So I was wondering if there were any manifestations of protest against handing of Poland to Stalin (in which process British government took active part)?
There was indeed. Whilst I'm unaware of specific instances of popular protest, I understand there was a strong and vociferous minority of politicians who risked much to decry HMG's (and specifically Churchill's) policy of appeasement to the Muscovites and treatment of Poland, consequent upon HMG's acquiescence to Stalin's designs for keeping what he had gained of Polish territory (Yalta).
The more relevant back stab was, in my view, the failure of HMG to tell Poland about the critical issues materialising out of Teheran, not to mention HMG’s craven acquiescence to Stalin. The backstab is even more serious because it was in breach, and in contempt, of HMG’s obligation to tell Poland (per Art. 5 of the Treaty) of any development that would threaten Poland’s independence.
Consequently, Poland was unaware that it was to be subject to significant and prejudicial changes to its borders and socio political makeup after the dust settled on WW2.
Stalin took it to mean that HMG probably couldn’t care less about what happened to Poland post WW2. Ergo, in my view, his actions, probably commencing at around the time of the Warsaw Rising and subsequently, should have come as no surprise to HMG and probably occurred in large part due to the fact that Stalin understood he had carte blanche and jurisdiction to do as he pleased in Poland, because HMG acquiesced to his designs as articulated at Teheran. As to what the USA did (or didn’t do), it’s largely irrelevant in this context because they were not contractually bound with Poland, morality aside.
The basest treachery lies in the fact that HMG continued to use Polish forces to continue fighting even after the treachery at Teheran, when the moral and just thing to do would have been to release the Poles, given that the Poles were now fighting for everything except their own interests. But no, this didn’t occur, because to do so would have been contrary to further British interests of using Poles (arguably the best contingent under HMG’s auspices numbering in the hundreds of thousands) to shed blood and die under the false assumption that they were fighting and dying for an ally and for mutual gain.
I think it was General Gubbins who articulated, in relation to HMG’s attitude to Poland, words to the effect that “we’ll squeeze as much as we can out of them then drop them”. Even that sentiment was incorrect, because in the early months of 1945 when Anders sought release of Polish forces to fight their way back home, he was refused. Bled dry, with pennies dropping all around him, how must Anders have felt to have been refused his request.
The story of HMG’s treachery toward Poland in WW2 is that simple. I believe that had the people of Britain known what was going on at the time they would have put a stop to it.