Can't tell you anything specific to your flight but I do know that the ZRH-TLV flight on LX has some overlap between J and F. For example, I've had occasion where I've been able to choose a F seat at check in, even though I was paying Z fare. Also, they provide complimentary upgrades to F for Honors Club members and to anyone else, for a relatively small (in the context of the distance and Class difference) fee. So...it wouldn't shock me if they provided F to deal with the baby in tow. Of course, it could also be a different configuration w/o F so I guess you will have to let us know.