Frequent but Intermittent crashes on IOS devices, 5.5.4

[step_jac_eg]

Hi Tuomas,

We believe the following changelists should provide resolution to this issue:

https://github.com/EpicGames/UnrealEngine/commit/c2f5dcbeb2936ff7fd2b9af8e2f3f6322505ce80

https://github.com/EpicGames/UnrealEngine/commit/330de5ad0c5f3712a2141905b1aa1e6a88f93951

Best regards.