How can we issue new appointment letter to everyone with proper CTC salary structure?

An employee joined a company in 2015 when there was no PF and ESI deduction and was getting salary only pt deductions
In September/October 2019, the employer implemented PF and ESI. Now, we also made some changes in our appointment letter and now We want to issue a new appointment letter to everyone with a proper CTC salary structure then How we could do?
His joining date in October 2015. Pf started in October 2019.
Please suggest so that I can write the same line on letters so that there should not be any confusion.. please note that we had issued an appointment letter when they have joined but now we want some updation on that... Please help me

Will it be valid?
Here we need to change duration of notice period...

@Mamta
in all appointments which are based on CTC, there are special allowance, which is just in lieu of ESIC/EPF or NPS and other employee beneficiary benefits
as soon as these schemes come in force or get implemented, the special allowance get reduced to the extent of the contributions,
fresh appointment letter is unwarranted, as it will generate a confusion in work team

Hi Mamta,

Pl.clarify, whether you are envisaging now to change from general category to CTC structure. If yes there is a purpose of formalising CTC regime. Otherwise just because PF deduction has been commenced in 2019 and that for this very purpose only you try to re-issue the appointment letter with modification has to be reconsidered. Having already implemented the PF deduction there's no need to notify this specifically for the simple reason that statutory deductions like PT, TDS, EPF/ESI suo moto apply to all pertinent pay roll whether you did mention or not. There is no scope to dispute applicability in the absence of specific mention about those in the appointment letter.

Perhaps you might as well wait till the time there is major change in emoluments such as promotion, revision of salary. And if and when it happens you might as well list all the relevant items as CTC and make it official for the concerned to understand the structure. Otherwise reissue a fresh appointment letter at this juncture just for the sake of EPF not advisable.