Is this mechanism correct?

#1

I am trying to solve Q.7

Here is my approach

I would like to know is my mechanism correct?

#2

#3

Sir why did you remove OR- in 4th step instead of OH- as oh- is more stable than or- and also in the next step R+ would be stabler than H+ during formaion of O=C

#4

See I form ketone by removing RO(-) Actually it is a hemiacetal form if I remove OH(-) and form ketone from RO then I have to remove R(-) group and it’s highly unstable.