1/The motte-and-bailey fallacy: common among evolutionists and CRT.
A motte-and-bailey castle design had a courtyard, the bailey, protected by relatively weak fortifications. If they were breached, the defenders could retreat to the more strongly defended motte.

2/ The bailey was more comfortable and often had markets and gardens, so it's where people preferred to be if they were not under attack. The motte had no function other than protection.

3/ The fallacy refers to advancing a very controversial position that is weakly defensible (the ‘bailey’). When the defences are breached, the argue retreat to a more defensible and non-controversial claim (the ‘motte’), and pretend that this was their argument all along.

4/ When the pressure is reduced, they return to the ‘bailey’, their indefensible argument.
For example:
Evolutionists: materialism explains everything, including the origin of first life from non-living chemicals (bailey).

5/ Creationists: [devastating counter from known laws of chemistry that evolutionists know they can't answer]
Evolutionists: evolution just means change of allele frequency over time (retreat to motte, since No ONE denies that allele frequency changes over time!).

6/ (This is also equivocation or bait-and-switch)
See explanation in https://heterodoxacademy.org/blog/the-motte-and-the-bailey-a-rhetorical-strategy-to-know/.