should i use OLCI or not?

I am flying PE on A346 and was hoping to get seats in row 18 A/C or H/J.
What is my best tactic?
Should i use olci, (i have seats right in front of the W/C)and try and change the seats at the airport or wait and check in normaly and try and get them there?
What is my best tactic?
Should i use olci, (i have seats right in front of the W/C)and try and change the seats at the airport or wait and check in normaly and try and get them there?