The former FT comms chief confirmed the Lib Dem line that she had resigned from the post due to the realisation that the position demanded more political focus than her corporate comms experience.
She told PRWeek: "I chose to leave because my strategic global, corporate-focused communications experience will be better used in a less day-to-day political operational role – and it's all very amicable."
The party said in a statement: "During the audit phase of the job, it became clear that the requirements of this position at this stage in the Parliament have a greater political and operational focus than the more corporate communications role that was originally envisaged, which is Emma's specialism.
"The work that Emma has done to identify the communications needs over the remaining period of this Parliament has been invaluable.
"We therefore wish Emma all the best and hope that we can work together again in the future."
Gilpin-Jacobs added: "I met some wonderful people within the Lib Dem party and wish them all the very best. We will keep in touch and may even work together again some day."
This story was updated at 13.25 to add a statement from Emma Gilpin-Jacobs.