@Francis_Vaughan is on the money. The oceans can be thought of as a complicated damped non-linear system, being driven at a couple of primary frequencies (twice per lunar day & twice per solar day). This system resonates at the driving frequencies but also at some of their harmonics, sum and difference frequencies, etc. Each oscillation at a particular frequency can be looked at separately, and these are called the “constituent tides”.
Here’s a map of the largest component of the tides: the so-called M2 constituent, which oscillates twice per lunar day. You can see that it’s not nearly as straightforward as “all points at the same latitude are at the same point in the tide cycle.” In particular, note that New Zealand & Madagascar are in the same situation as PEI: when it’s high tide on one side of the island(s), it’s low tide on the other. I believe this is the case for the British Isles as well, though it’s hard to tell from this animation alone.
