This was definitely a formalisation of a practice which had been initially introduced in February. This is typical of the Luftwaffe.
An ULTRA decrypt of 12 February ('44) was an order for the spinner spiral recognition marking to be applied on fighter aircraft (specifically) operating in the Reich and with Luftflotte 3, in France.
On 25th June an order seemed to remove all other tactical markings, probably in response to the allied 'Special Markings' (invasion stripes etc) and just retain the spinner spiral, national markings, kennziffer and group marks.
On 29th June a message to Luftflotte 3 said that additional tactical markings should be retained, which evidently caused some confusion.
The 20th July order quoted in part in my original answer was supposed to be a clarification.