MOO: I believe MR is actually telling the truth on this point. He saw Dylan texting on his Ipod and argued with LE that Dylan had been texting later on in the evening (much to his annoyance, probably). LE, in the mean time, had the cell records that showed Dylan stopped sending texts from his cell phone around 8:00 (I think MR confiscated it or perhaps there wasn't good reception in parts of the house). So, until it occured to LE that Dylan had used a different device, they would be argue about it.
If MR had killed Dylan earlier, he wouldn't argue that Dylan had kept texting. Surely he'd know LE could get the cell records. He'd make his story fit the cell phone record. IMO. MOO.