According to the BBFC for films up to and including a 15 certificate:
'Discrimination
The work as a whole must not endorse discriminatory language or behaviour.'
So if they wanted to keep the name, and not be an 18 certificate, they'd have to a long explanation to camera about how the name was ok for the time, but is now strictly verboten.
I'm not too bothered about the change. The b&w original film will always be around, and the name of the dog is largely an irrelevance.
I'm more interested about how they will explain the inspiration for the twin spotlights used to gauge the height of the plane off the water. You will have to explain to modern audiences how things called 'theatres' used to exist, and real people would be on stage and perform and stuff. It would even be in 3D, without the need for glasses.
For another snippet of things that are never taught and rarely mentioned, after the initial massive casualties of WW1, the allies employed over 100,000 Chinese to dig the trenches....