Pickerill reportedly plans to leave the Royal Household completely and move overseas after finishing up with the duchess - but she plans to stick around long enough to help Meghan through those crucial first few months as a royal mum.
For the latest on Markle and her pregnancy, watch below.
Amy first started her career at Kensington Palace as a press spokesperson and was "instrumental in helping the duchess adjust to her new life in the United Kingdom", the source shared before adding, "they have worked together for a while now and are close".
It comes just three months after it was reported that the Duchess' top aide Samantha Cohen will be leaving her role following the birth of the royal baby, with Ms Pickerill tipped to succeed her until now.
Pickerill was also responsible for the former Suits star's diary, as well as preparing her briefs ahead of every ahead of every royal engagement.
The personal assistant is believed to have limited the PR damage after Meghan's father Thomas Markle was caught in a photo faking scandal before the royal wedding.
A report claims Meghan Markle and Prince Harry are anxious about their safety.
She said: "I don't read anything, it's much safer that way, but equally that's just my own personal preference because I think positive or negative it can all sort of just feel like noise to a certain extent these days, as opposed to getting muddled with that to focus on the real cause".
Kensington Palace declined to comment on the reports, but an insider did pay tribute to the PA.
Since his courtship with his left-liberal wife began, however, things have changed, with his relationship with older brother Willian and sister-in-law Kate allegedly becoming strained, with one correspondent warning the prince should be careful not to "turn himself into some celebrity" who people will "tire of".