Previously my company also flows the same pattern of salary cycle. Whenever such type of situation arises we include 27th day of month so that it get will get adjusted with the law also. Means for the month of may salary i.e. from 26 June to 26 May total 31 days. And for the salary of June - 27 May to 25 June total day for the month of June salary will be 30. I think that this will solve your problem and company also not fall under any legal trap.