The changes brought about by HC1087 , which came into force on 6 April 2017, were contained within a document consisting of a sizeable number of 269 pages. One such change was clarification as to validity of applications that are pending at the same time.
This situation can occur where an applicant who qualifies under two rules makes an application for both on the same date, or applies under one rule and then follows through with another application whilst the first remains undecided.
The rules now have the addition of a paragraph that deals with such situations. This can be found within part 1 of the Immigration Rules at paragraph 34BB:
(1) An applicant may only have one outstanding application for leave to remain at a time.
(2) If an application for leave to remain is submitted in circumstances where a previous application for leave to remain has not been decided, it will be treated as a variation of the previous application.
(3) Where more than one application for leave to remain is submitted on the same day then subject to sub-paragraph (4), each application will be invalid and will not be considered.
(4) The Secretary of State may give the applicant a single opportunity to withdraw all but one of the applications within 10 working days of the date on which the notification was sent. If all but one of the applications are not withdrawn by the specified date each application will be invalid and will not be considered.
(5) Notice of invalidity will be given in writing and served in accordance with Appendix SN of these Rules."
The safety measure is of course the discretion of the home office to provide the applicant with a single opportunity to withdraw one of the applications. As with all things discretionary, caution must however be exercised to avoid the dreaded consequences of an invalid application.