Need help with if(and formula.

Hi there,

i have been trying to create a formula lately but with no sucess. What is has to do is in cell C6 it should bring up text given in cell a100 or a101.
To explain the spreadsheet, it basically shows the times for each phase. If the actual start/finish dates are entered higher than planned start/finished, it should make cell C6 pick A100(Late) if not cell A101 (on schedule). PROBLEM: if the time in next actual start phase (Actual start for BOM Approved F12) keeps exceeding the planned E12, it should keep A100, if not, take A101 and so on until the last time in H13.

It is hard to explain what i acutally need as english is not my mother language but any help would be apreciated. Is there any other formula i could use, that would look at the time entered, if its FALSE(formula) and next one is TRUE and the next after FALSE again, it should change the cell C6 according if its false or true.
Picture added as attachment, let me know if anything else is needed.