I always change mineral oil within 5-6k kms. Will not recommend you to use till 10k.
Source :
Good Reasons for Switching to Synthetic Oil | United States
Let's say , You are spending 4k on synthetic oil to use for 2 years.
Why dont you spend 1400rs every year on semi synthetic ?
Dont go for mobil 0w40 fully synthetic. It's unfeasible.
Don't get confused more. Get castrol semi synthetic and get it changed every year.
Btw what's your swift's interval period ?