Refresher training 
Once any of the instructor certificate is expired - to re-gain its privileges, the renewal training iaw FCL.940.FI and AMC1 FCL940.FI has to be followed. The renewal procedure is so-called Refresher training. The Refresher training is also required by FCL.940.IRI and AMC1 FCL.940.IRI for renewal of IRI(A) certificate.
The difference between the Refresher training and Refresher seminar established by Part FCL is important.
Refresher Seminar is theoretical knowledge instruction and workshop required by Part FCL as one of the conditions for revalidation of particular instructor certificate. While Refresher training is the renewal procedure required by Part FCL to re-gain the instructor privileges. Due that fact the Refresher training consists of flight training and Refresher Seminar itself.  To make it simple - besides the Flight training, the Refresher Training contains also the Refresher Seminar as a mandatory part of the Refresher Training.
If the instructor certificate lapsed, the ATO or competent authority should consider following, when assessing the refresher training programme:
amount of refresher training needed, following an assessment of the candidate taking into account the following factors:
the experience of the applicant;
the amount of time elapsed since the expiry of the FI or IRI certificate; and
the technical elements of the FI or IRI training course, as determined by the assessment of the candidate
The individual training programme should be based on the content of the FI or IRI training course and focus on the aspects where the applicant showed the greatest needs.