Probably. The issue is that Corbyn simply has not had the extreme defeats that the right of Labour want him to have. Without those defeats, they don't really have a legitimate reason to throw out Corbyn, other than to perhaps re-run a leadership election which he would win regardless. The party is now set up in a way that Corbyn wins whatever the moves will be by the right, he's using the same tactics as Trump really. He has moved the frames to such a level that anything the opposition does is automatically your win. They don't have a choice until Corbyn fucks up like never before. Since 2016 elections are the last elections before 2020 with any significant party political movements (just locals until 2020), then Corbyn's mandate cannot really be questioned. I mean, Labour has already reached the lowest poll numbers with Corbyn since the depths of 2009 where they were rammed into the wall, and yet Corbyn still survived under the clout of "the media/establishment is against me, they are running these untrue polls, look at how I survived all the elections" line.
If Corbyn is to go down in a coup, it will be because of abnormally low poll numbers around 25% somewhere between now and 2020. He won't go down because of any elections. Alternatively, we'll go back to 1980s and the right Labour will just leave, though that has decreasing likelihood imho.
To be honest this depends entirely on what we mean by "save". I don't think Labour will ever be eligible to get a parliamentary majority again. Scotland and England have fked them up. Even if they miraculously got Scotland back through some voodoo sorcery at 5000 / 1 odds, EVEL will still fk them up.
In terms of returning Labour to the rightful place of the opposition at mid-term - poll plurality - I think they are still able to do it if they get a unifying candidate. At the end of the day most Corbyn voters are children freshly out (or still in) of university and really old Labour marxists so not like they will refuse to vote Labour if he gets thrown out. There will just be initial turmoil.