User blog comment:FairyRaven/Fairy Tail Chapter 336: In Order to Live Today to the Fullest, Review and Commentary/@comment-7418318-20130621152145/@comment-4643135-20130622034816

I only have a few guesses how it could work. We see that F-Lucy has been in the present for at least a couple of days and maybe she came back with her keys. In that time, she might have had Crux do some research on the gate which is how she would know about the link it has to maintain when used. (If she had to use p-Crux because of being she can't summon him from different times, then he could have also already known about the gate reaching 400 years into the past in the circumstances and wanted to warn her.[I doubt he could have done the search in the time between knocking out the Order of the Hungry Wolves and when they catch up to the princess and Arcadios])

I have no idea really for her finding the journal. I know she's Lucky Lucy but it has to have some limits.

Did the guard say it was illegible in the sense that her handwriting was poor or was it in the sense that he didn't understand the context of what she wrote? The guard may not be fully aware of the Eclipse plan and so would not understand what the gate is or anything related to it. But since P-Lucy and Yukino are frightfully aware, it would make sense to them.

I'm just throwing some ideas around. That's all anyone really can do when commenting.