question concerning standard possession order

i am in texas. i need to ask a question concerning extended summer visitation. do you have to go by your papers if in them it says that you should follow the standard possession order from the texas family code? my papers said that if the managing conservator gives notice by june 1st, he could exercise one weekend during summer visitation. legislation ammended that rule to read that the managing conservator gives notice by april 15th, he could have one weekend during summer visitation. so i need to know which date to go by. the new amended version or what is in my papers. by the way, he gave me notice may 3. i really don't want to make my son go for that weekend because we are having some paternity issues going on at the same time and my son is 13 and doesn't really want to go for that particular weekend because he is afraid what his presumed father will say or do. he hasn't been at my house for over a month. i know it's hard not to see either parent for that length of time, but i had to wait a month to see him so why shouldn't he. also maybe we will have the paternity issue over by the end of the month. this probably didn't make sense and i'm sorry, there is alot going on that i won't go into. so, kinda ignore most of what i said and please answer the question about which law to follow. thank you.