"Sent from my iPhone" injected line when customer replies to request on a mobile device not being stripped and affects confidence levels

[AndyBoatwright]

Bug description
Where customers respond to ALC requests or generally reply, if they are sending in from a mobile device app, the email format and layout automatically inserts a line "Sent from iPhone" or similar; this injected line adds additional complexity to the query as it's not being stripped as part of a signature, and remains in the body text.

Reference number(s)
North UAT -EMN001432; EMN001431

Expected behaviour
Ignore wording injected into body text when customers are replying to requests on a mobile device that is purely because it's indicating that this is the case.

Issue does not appear to have notable effect when using Outlook on Mobile, even though a message line is injected; may only be an issue with Apple devices?