Don't know, don't care.
This is not a precise process. The advantage of stringing them along is the possibility of timing out the offence - them continuing this silly dance until it is too late to instigate court proceedings. Clearly not going to happen.
The fact that you have received a reminder out of the sequence you were expecting at most means that court proceedings might be instigated sooner than you were expecting, or that the polis might start lurking in your garden sooner than you were expecting.
Case law (Scottish) tells us that (for the purposes of instigating proceedings at least) there is only one s. 172 offence committed (if it is committed at all), and that is committed at the expiration of the original 28 days. Subsequent reminders are nothing more than a kind offer to "undo" the offence by complying with the requirements out of time.
The fact that the template letter says "no response", rather than "no acceptable response" is neither here nor there - beyond showing the level of diligence and intelligence being expended upon this matter.
The 6 months for any s. 172 offence is committed at the expiration of the 27 days from (28 days beginning with) the date of service of the original notice to that person (which in E&W is deemed to be 2 working days after posting).
Where your case potentially differs from the standard unsigned case in Scotland, is that you [presumably] utterly failed to respond to the original notice sent to your previous address. If they were to expend any diligence or intelligence on this case, that would seem to be a slam dunk easy win for them if it were to go to contested trial. In E&W it could be argued that prosecuting for the original failure if a subsequent reminder was complied with would be an abuse of process. However, this would leave the question of whether incomplete compliance with the stated requirement was sufficient to render the prosecution an abuse, and as I understand it, abuse of process isn't a thing north of the border.
