Evoque 2016 oil service at dealership vs other garages/CT/Shell

Hi Friends,

I bought a certified 2016 RR Evoque SE gasoline in Feb 2020 with an
extended warranty until Sep 2022.

this car is currently due for service (52000kms)



The dealer ship  quoted $750 ( Oil change+filter + Air/ cabin/ pollen filter
and routine checkup)



But since  I am planning to sell this vehicle sooner or later, hence looking for
some after-market parts( Castrol synthetic oil + FRAM/Mobile 1 filters etc). I
know the dealership will check all the mechanics/electronics of the car
during this service but the after-market guy won't. I am a bit scared if this
might void my warranty in the future run.



Moreover, JLR recommends Castrol edge Pro C1- A5 5w-30 which is
available only at the dealership not anywhere else. I am getting Castrol
Edge Extra performance oil 5w-30 in nearby stores.

my other trusted garage is SHELL but they use only SHELL products.



Need your expert advice on :

1. if I should go to the dealership or other garage ( CT/Shell ..)??

2. If other garages, can I use equivalent  SHELL oil instead of CASTROL ??

3. If not SHELL, can I use Castrol edge Extra perf oil instead of Castrol
edge pro??



I am totally confused and need your expert advice.