Doesn't look unreasonable as they are not forcing a change for existing users and some low usage customers could save.
Personally though I prefer unlimited access for £23.44 a month from Pipex
OnePlus 5T review: Hands-on
Illustrator Andrés Lozano on his improv line work, brazen use of colours & hand sketching
iPhone X review
Comment envoyer gratuitement des gros fichiers ?