You should get unionised
It sounds like a unilateral change of contract
which you havent agreed to and will involve you in loss.
My employer sudduv did the same to us (I am now retired and I would likek to say the employer threw a party for themselves...)
(not pay sick pay when we were ick)
and this is what we did to him (CMFT Manchester).
"The Royal College of Nursing today (February 23) called for all NHS employers to uphold agreed terms and conditions for staff after winning an important test case at an employment tribunal.
The RCN, alongside Unison and Unite, were successful in challenging a decision by Central Manchester Hospitals Foundation Trusts (CMFT) to withhold incremental pay rises for 83 staff on the basis of their sick records. The NHS Agenda for Change pay agreement provides a contractual entitlement for NHS staff to receive a certain number of pay increments in each grade as they gain greater competence and experience.
The trust withheld increments from staff whose reasons for taking sick leave included being physically assaulted by a patient, and recovering from major surgery. The tribunal found that this constituted an unlawful deduction of pay and that the Trust must repay those deductions to the claimants."
The trust lost the nurses' and ancillary staff case
and didnt take on the doctors' in the High Court
having been told continuously for two years they would lose....
and the BMA claimed their costs against the Trust (£135k)
basically you wait for a loss and then take them to court
but it does cost....
hence the union advice
this is the sort of case they love to take on