‘
Lumps’ or perhaps a step change.
A marked change in the number of ‘spam’ messages (iPad, iOS 14.4), some getting though the gmail filter.
An evolving spam technique, or because of a
sandboxed 'BlastDoor'.
https://catless.ncl.ac.uk/Risks/32/48#subj2
‘Google uncovers new iOS security feature’
P.S. the ‘new’ recent spam messages have a similar format:-
Limited address list, 3 - 4, neither origin or cc addresses known to me,
a pdf attachment (content unknown, never opened)