I browsed the options mentioned by you.
You have mentioned that there is no salary hike on probation and the increment is only on Jan.
We also have a similar type of practise.
So to address such type of issues we give a nominal hike in the salary for the employees under probation( say 10% prorata basis) and then in the next year they come on the normal salary hike as per the company's policy.
Ex: An employee has joined in March 10. As per policy he is due for confirmation on March 11 and due for increment on Jan 12.
On Jan 11 the employee will be awarded a nominal hike of 10%(Prorata) and will be eligible for normal hike from Jan 12.
Hope my reply would be of some help. for You
Girija A M